Feeling Blue

I've been ttc my first for almost two years. I'm turning 43 in a few weeks and I'm starting to really get upset about my age and not being a mother. Today I was with my 11 year old niece and nephews that I lived with the first four years of their life. They are the closest I have to children and I love them so much. After I dropped them off today, I had an overwhelming feeling of sadness. I'm starting to feel like I'm never going to experience what it feels like to be a mother. I feel like I'm missing out on something so special. I normally I don't let it get to me like this. However,  today I've been crying on and off all day because I so desperately want to be a mother! Sorry for going on about this, I just needed to get it off my chest!